Display device, electronic device having display device and method of operating the same

ABSTRACT

A display device includes a display panel including a plurality of pixels, a scan driving unit configured to provide a scan signal to the pixels, a data driving unit configured to provide a data signal to the pixels, and a controller configured to provide driving frequency information to a processor, which transfers image data with a driving frequency determined based on the driving frequency information to the display device, to receive the image data with the driving frequency from the processor, and to control the scan driving unit and the data driving unit to drive the display panel with the driving frequency.

This application is a continuation of U.S. patent application Ser. No.16/740,842, filed on Jan. 13, 2020, which is a divisional of U.S. patentapplication Ser. No. 14/583,728, filed on Dec. 28, 2014, which claimspriority to Korean patent Application No. 10-2014-0060967 filed on May21, 2014, and all the benefits accruing therefrom under 35 U.S.C. § 119,the content of which in its entirety is herein incorporated byreference.

BACKGROUND 1. Field

Exemplary embodiments of the invention relate to a display device. Moreparticularly, exemplary embodiments of the invention relate to a displaydevice, an electronic device including the display device, and a methodof operating the display device.

2. Description of the Related Art

Generally, an image displayed by a display device is classified into astill image and a moving image. The still image is displayed when thedisplay device displays several frames per second, and data of eachframe are the same as each other, for example. The moving image isdisplayed when the display device displays several frames per second,and data of each frame are different from each other, for example. Whenthe still image is displayed, the display device receives the image datafrom a processor for every frame to display the still image, therebyincreasing power consumption.

Recently, a method of operating an electronic device including thedisplay device is developed to reduce the power consumption. In such amethod, a frame memory is used to the display device to store the imagedata of the still image, and the stored image data are provided to thedisplay panel while the still image is displayed. This is referred to asa pixel self-refresh (“PSR”) technique. In the PSR technique, the imagedata are not transmitted from the processor while the still image isdisplayed such that the processor is not activated, thereby reducing thepower consumption. In another method to reduce the power consumption,the display device without the frame memory may generate control signalscorresponding to the image data with a low frequency when the image dataare still image data.

SUMMARY

In the PSR technique, power is consumed in the frame memory andmanufacturing cost may also increase when the frame memory is added tothe display device. In a method, where the display device without theadditional frame memory generates control signals corresponding to theimage data with a low frequency when the image data are still imagedata, it may be difficult to reduce the driving frequency between theprocessor and the display device.

Exemplary embodiments provide a display device with reduced powerconsumption without additional manufacturing cost.

Exemplary embodiments provide an electronic device including the displaydevice and the processor.

Exemplary embodiments provide a method of operating the electronicdevice.

According to some exemplary embodiments, the display device may includea display panel including a plurality of pixels, a scan driving unitconfigured to provide a scan signal to the pixels, a data driving unitconfigured to provide a data signal to the pixels, and a controllerconfigured to provide driving frequency information to a processor,which transfers image data with a driving frequency determined based onthe driving frequency information to the display device, to receive theimage data with the driving frequency from the processor, and to controlthe scan driving unit and the data driving unit to drive the displaypanel with the driving frequency.

In exemplary embodiments, the controller may include an image datareceiving unit configured to receive the image data from the processor,a still image determining unit configured to determine whether the imagedata are still image data, a driving frequency deciding unit configuredto decide the driving frequency by analyzing the image data when theimage data are the still image data, a frequency information providingunit configured to provide the driving frequency informationcorresponding to the driving frequency to the processor, and a timingcontroller configured to generate control signals based on the imagedata, and to provide the control signals to the scan driving unit andthe data driving unit.

In exemplary embodiments, the driving frequency deciding unit maycalculate a grayscale of the image data, and decide the drivingfrequency based on the grayscale of the image data using a flickerprofile of the display device.

In exemplary embodiments, the controller may include an image datareceiving unit configured to receive the image data from the processor,a driving frequency deciding unit configured to decide the drivingfrequency by analyzing the image data, a frequency information providingunit configured to provide the driving frequency informationcorresponding to the driving frequency to the processor, and a timingcontroller configured to generate control signals based on the imagedata, and to provide the control signals to the scan driving unit andthe data driving unit.

In exemplary embodiments, the controller may include a profile providingunit configured to provide a flicker profile of the display device asthe driving frequency information to the processor, an image datareceiving unit configured to receive the image data with the drivingfrequency determined based on the flicker profile from the processor,and a timing controller configured to generate control signals based onthe image data, and to provide the control signals to the scan drivingunit and the data driving unit.

According to some exemplary embodiments, an electronic device mayinclude a display device configured to receive image data from aprocessor, to display an image corresponding to the image data, and toprovide driving frequency information to the processor, and theprocessor configured to receive the driving frequency information, toadjust a frequency of the image data based on the driving frequencyinformation, and to transfer the image data with the adjusted frequencyto the display device.

In exemplary embodiments, the display device may include a display panelincluding a plurality of pixels, a scan driving unit configured toprovide a scan signal to the pixels, a data driving unit configured toprovide a data signal to the pixels, and a controller configured toprovide the driving frequency information to the processor, to receivethe image data with the adjusted frequency from the processor, and tocontrol the scan driving unit and the data driving unit to drive thedisplay panel with the adjusted frequency.

In exemplary embodiments, the controller may include an image datareceiving unit configured to receive the image data, a still imagedetermining unit configured to determine whether the image data arestill image data, a driving frequency deciding unit configured to decidea driving frequency by analyzing the image data when the image data arethe still image data, a frequency information providing unit configuredto provide the decided driving frequency as the driving frequencyinformation to the processor, and a timing controller configured togenerate control signals based on the image data with the adjustedfrequency, and to provide the control signals to the scan driving unitand the data driving unit. In such an embodiment, the processor mayinclude a frequency information receiving unit configured to receive thedecided driving frequency as the driving frequency information from thefrequency information providing unit, and an image data transferringunit configured to adjust the frequency of the image data to the decideddriving frequency, and to transfer the image data with the decideddriving frequency to the image data receiving unit.

In exemplary embodiments, the driving frequency deciding unit maycalculate a grayscale of the image data, and decides a driving frequencycorresponding to the grayscale of the image data as the decided drivingfrequency using a flicker profile of the display device.

In exemplary embodiments, the image data transferring unit may adjustthe frequency of the image data to the decided driving frequency bymasking the image data.

In exemplary embodiments, the processor may further include an imagedata memory configured to store the image data, and the image datatransferring unit may adjust the frequency of the image data to thedecided driving frequency using the image data memory.

In exemplary embodiments, the frequency information providing unit mayprovide the decided driving frequency to the frequency informationreceiving unit when the driving frequency is changed.

In exemplary embodiments, the frequency information receiving unit mayperiodically send a driving frequency providing request to the frequencyinformation providing unit, and the frequency information providing unitmay provide the decided driving frequency to the frequency informationreceiving unit in response to the driving frequency providing request.

In exemplary embodiments, the controller may include an image datareceiving unit configured to receive the image data, a driving frequencydeciding unit configured to decide a driving frequency by analyzing theimage data, a frequency information providing unit configured to providethe decided driving frequency as the driving frequency information tothe processor, a timing controller configured to generate controlsignals based on the image data with the adjusted frequency, and toprovide the control signals to the scan driving unit and the datadriving unit. In such an embodiment, the processor may include afrequency information receiving unit configured to receive the decideddriving frequency as the driving frequency information from thefrequency information providing unit, a still image determining unitconfigured to determine whether the image data are still image data, andan image data transferring unit configured to adjust the frequency ofthe image data to the decided driving frequency when the image data arethe still image data, and to transfer the image data with the decideddriving frequency to the image data receiving unit.

In exemplary embodiments, the controller may include a profile providingunit configured to provide a flicker profile of the display device asthe driving frequency information, an image data receiving unitconfigured to receive the image data with the adjusted frequency fromthe processor, and a timing controller configured to generate controlsignals based on the image data with the adjusted frequency, and toprovide the control signals to the scan driving unit and the datadriving unit. In such an embodiment, the processor may include a profilereceiving unit configured to receive the flicker profile correspondingto the driving frequency information from the profile providing unit, astill image determining unit configured to determine whether the imagedata are still image data, a driving frequency deciding unit configuredto calculate a grayscale of the image data when the image data are thestill image data, and to decide a driving frequency corresponding to thegrayscale of the image data using the flicker profile, and an image datatransferring unit configured to adjust the frequency of the image datato the decided driving frequency, and to transfer the image data withthe decided driving frequency as the image data with the adjustedfrequency to the image data receiving unit.

In exemplary embodiments, the profile providing unit may provide theflicker profile to the profile receiving unit when the display device isinitialized.

In exemplary embodiments, the display device may include a display panelincluding a plurality of pixels, and a plurality of integration drivingunits configured to provide the driving frequency information to theprocessor, to receive the image data with the adjusted frequency fromthe processor, and to drive the display panel with the adjustedfrequency.

In exemplary embodiments, the processor may receive the drivingfrequency information from the integration driving units, and adjuststhe frequency of the image data to the highest driving frequency among aplurality of driving frequencies corresponding to the driving frequencyinformation from the integration driving units, respectively.

According to some exemplary embodiments, a method of operating anelectronic device including a processor and a display device may includedetermining whether image data are still image data, calculating agrayscale of the image data when the image data are the still imagedata, deciding a driving frequency corresponding to the gray scale usinga flicker profile of the display device, adjusting a frequency of theimage data based on the decided driving frequency using the processor,transferring the image data with the adjusted frequency from theprocessor to the display device, and displaying an image correspondingto the image data using the display device.

In exemplary embodiments, the frequency of the image data may beadjusted to the driving frequency by masking the image data.

In such embodiments, where the display device provides driving frequencyinformation to the processor such that the processor transfers imagedata with a driving frequency determined based on the driving frequencyinformation, the display device may be driven at a low frequency,thereby reducing the power consumption. In such embodiments, where thedisplay device does not include a frame memory that stores the imagedata of the still image, the manufacturing cost of the display devicemay be reduced.

In such embodiments, the electronic device may reduce the powerconsumption by performing a low frequency driving between the processorand the display device.

In such embodiment, a method of operating an electronic device mayeffectively prevent the flicker and reduce the power consumption byperforming a low frequency driving using a flicker profile.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other features of the invention will become more apparentby describing in detailed exemplary embodiments thereof with referenceto the accompanying drawings, in which:

FIG. 1 is a block diagram illustrating an exemplary embodiment of anelectronic device according to the invention;

FIG. 2 is a block diagram illustrating an exemplary embodiment of aprocessor and a controller of a display device of the electronic deviceof FIG. 1 ;

FIG. 3 is a graph showing an exemplary embodiment of a flicker profileto decide a driving frequency in the electronic device of FIG. 1 ;

FIG. 4 is a diagram illustrating an exemplary embodiment of a lowfrequency driving between the processor and the display device of FIG. 2;

FIG. 5 is a block diagram illustrating another exemplary embodiment of aprocessor and a controller of a display device of the electronic deviceof FIG. 1 ;

FIG. 6 is a block diagram illustrating still another exemplaryembodiment of a processor and a controller of a display device of theelectronic device of FIG. 1 ;

FIG. 7 is a block diagram illustrating still another exemplaryembodiment of a processor and a controller of a display device of theelectronic device of FIG. 1 ;

FIG. 8 is a diagram illustrating an exemplary embodiment of a lowfrequency driving between the processor and the display device of FIG. 7;

FIG. 9 is a block diagram illustrating another exemplary embodiment ofan electronic device according to the invention;

FIG. 10 is a block diagram illustrating an exemplary embodiment of aprocessor and an integration driving units of a display device of theelectronic device of FIG. 9 ; and

FIG. 11 is a flow chart illustrating an exemplary embodiment of a methodof operating an electronic device according to the invention.

DESCRIPTION OF EMBODIMENTS

The invention now will be described more fully hereinafter withreference to the accompanying drawings, in which various embodiments areshown. This invention may, however, be embodied in many different forms,and should not be construed as limited to the embodiments set forthherein. Rather, these embodiments are provided so that this disclosurewill be thorough and complete, and will fully convey the scope of theinvention to those skilled in the art. Like reference numerals refer tolike elements throughout.

It will be understood that when an element is referred to as being “on”another element, it can be directly on the other element or interveningelements may be therebetween. In contrast, when an element is referredto as being “directly on” another element, there are no interveningelements present.

It will be understood that, although the terms “first,” “second,”“third” etc. may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are only used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, “a first element,” “component,” “region,” “layer” or“section” discussed below could be termed a second element, component,region, layer or section without departing from the teachings herein.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms, including “at least one,” unless the content clearly indicatesotherwise. “Or” means “and/or.” As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items. It will be further understood that the terms “comprises”and/or “comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

Furthermore, relative terms, such as “lower” or “bottom” and “upper” or“top,” may be used herein to describe one element's relationship toanother element as illustrated in the Figures. It will be understoodthat relative terms are intended to encompass different orientations ofthe device in addition to the orientation depicted in the Figures. Forexample, if the device in one of the figures is turned over, elementsdescribed as being on the “lower” side of other elements would then beoriented on “upper” sides of the other elements. The exemplary term“lower,” can therefore, encompasses both an orientation of “lower” and“upper,” depending on the particular orientation of the figure.Similarly, if the device in one of the figures is turned over, elementsdescribed as “below” or “beneath” other elements would then be oriented“above” the other elements. The exemplary terms “below” or “beneath”can, therefore, encompass both an orientation of above and below.

“About” or “approximately” as used herein is inclusive of the statedvalue and means within an acceptable range of deviation for theparticular value as determined by one of ordinary skill in the art,considering the measurement in question and the error associated withmeasurement of the particular quantity (i.e., the limitations of themeasurement system). For example, “about” can mean within one or morestandard deviations, or within ±30%, 20%, 10%, 5% of the stated value.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It willbe further understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and thedisclosure, and will not be interpreted in an idealized or overly formalsense unless expressly so defined herein.

Exemplary embodiments are described herein with reference to crosssection illustrations that are schematic illustrations of idealizedembodiments. As such, variations from the shapes of the illustrations asa result, for example, of manufacturing techniques and/or tolerances,are to be expected. Thus, embodiments described herein should not beconstrued as limited to the particular shapes of regions as illustratedherein but are to include deviations in shapes that result, for example,from manufacturing. For example, a region illustrated or described asflat may, typically, have rough and/or nonlinear features. Moreover,sharp angles that are illustrated may be rounded. Thus, the regionsillustrated in the figures are schematic in nature and their shapes arenot intended to illustrate the precise shape of a region and are notintended to limit the scope of the claims.

Hereinafter, exemplary embodiments of the invention will be described indetail with reference to the accompanying drawings.

FIG. 1 is a block diagram illustrating an exemplary embodiment of anelectronic device according to the invention.

Referring to FIG. 1 , an exemplary embodiment of an electronic device1000A may include a display device 100A and a processor 200.

The display device 100A may include a display panel 110A, a scan drivingunit (e.g., a scan driver) 130, a data driving unit (e.g., a datadriver) 150, and a controller 170. In an exemplary embodiment, thedisplay device 100A may provide driving frequency information FRI to theprocessor 200, receive image data DATA with the driving frequencydetermined based on the driving frequency information FRI from theprocessor 200, and display an image corresponding to the image dataDATA.

The display panel 110A may include a plurality of pixels to displayimage. The display panel 110A may be coupled to the scan driving unit130 via scan lines, and may be coupled to the data driving unit 150 viadata lines. The display panel 110A may include the pixels that connectedto the scan-lines and the data-lines. In one exemplary embodiment, forexample, the pixels are arranged at locations corresponding to crossingpoints of the scan-lines and the data-lines.

The scan driving unit 130 may provide a scan signal to the pixels of thedisplay panel 110A via the scan-lines.

The data driving unit 150 may provide a data signal to the pixels of thedisplay panel 110A via the data-lines.

The controller 170 may provide the driving frequency information FRI tothe processor 200, receive the image data DATA with the drivingfrequency determined based on the driving frequency information FRI fromthe processor 200, and control the scan driving unit 130 and the datadriving unit 150 to drive the display panel 110A with an adjustedfrequency, that is, the driving frequency adjusted or determined basedon the driving frequency information FRI.

Thus, the controller 170 may provide the driving frequency informationFRI based on the size or type of the display device 100A, such that thecontroller 170 receive the image data DATA with the adjusted drivingfrequency corresponding to the display device 100A from the processor200. In an exemplary embodiment, the driving frequency information FRIincludes various kinds of information to decide or determined thedriving frequency. In one exemplary embodiment, for example, the drivingfrequency information FRI may include a flicker profile that involvesdriving frequencies corresponding to grayscale of the image data DATA toeffectively prevent the flicker. In another exemplary embodiment, thedriving frequency information FRI may include the driving frequencydetermined based on the grayscale of the image data DATA and the flickerprofile.

The controller 170 may control the scan driving unit 130 and the datadriving unit 150 by providing the control signals corresponding to theimage data DATA to the scan driving unit 130 and the data driving unit150. In one exemplary embodiment, for example, the controller 170 maygenerate a data signal DATA1, a first clock signal CLK1 and a horizontalstart signal STH, and may provide the data signal DATA1, the first clocksignal CLK1 and the horizontal start signal STH to the data driving unit150. The controller 170 may generate a second clock signal CLK2 and avertical start signal STV, and may provide the second clock signal CLK2and the vertical start signal STV to the scan driving unit 130.

In such an embodiment, the display device 100A may further include apower supply unit (e.g., a power supplier) that supplies the power tothe pixels.

The processor 200 may receive the driving frequency information FRI,adjust a frequency of the image data DATA based on the driving frequencyinformation FRI, and transfer the image data DATA to the display device100A. In one exemplary embodiment, for example, when the image data DATAare the still image data, the processor 200 may adjust the frequency ofthe image data DATA corresponding to the driving frequency informationFRI that is received from the display device 100A, and may transfer theimage data DATA with a low frequency (e.g., a frequency lower than anormal driving frequency when the image data DATA is not the still imagedata) to the display device 100A. The processor 200 may include variouskinds of devices that process the image data DATA and transfer the imagedata DATA to the display device 100A. In one exemplary embodiment, forexample, the processor 200 may be an application processor (“AP”), amicro control unit (“MCU”), etc.

Therefore, in an exemplary embodiment, the electronic device 1000Aincludes the display device 100A that provides the driving frequencyinformation FRI and the processor 200 that adjusts the frequency of theimage data DATA based on the driving frequency information FRI, therebyperforming a low frequency driving between the processor 200 and thedisplay device 100A and reducing the power consumption. In such anembodiment, the display device 100A may not include a frame memory thatstores the image data, thereby reducing manufacturing cost.

FIG. 2 is a block diagram illustrating an exemplary embodiment of aprocessor and a controller of a display device of the electronic deviceof FIG. 1 .

Referring to FIG. 2 , in an exemplary embodiment, a controller 170A ofthe display device may provide the driving frequency to the processor200A as the driving frequency information FRI, such that the processor200A may adjust a frequency of the image data based on the drivingfrequency.

In an exemplary embodiment, the controller 170A may include an imagedata receiving unit 171, a still image determining unit 172, a drivingfrequency deciding unit 173, a frequency information providing unit 174and a timing controller 178. In one exemplary embodiment, for example,the controller 170A may a circuit (e.g., an integrated circuit such as adata processor, etc.), and units of the controller 170A may be a portionof the controller 170A that perform predetermined operations therein.

In such an embodiment, the image data receiving unit 171 may receive theimage data from an image data transferring unit 240. The image datareceiving unit 171 may transfer the image data to the still imagedetermining unit 172 to decide the driving frequency between theprocessor 200A and display device. In such an embodiment, the image datareceiving unit 171 may transfer the image data to the timing controller178 to provide control signals corresponding to the image data to thescan driving unit and the data driving unit.

The still image determining unit 172 may determine whether the imagedata from the image data receiving unit 171 are still image data. In oneexemplary embodiment, for example, the still image determining unit 172may analyze the frame data of the image data. When data of each frameare not changed during predetermined frame periods, then the image dataare determined to be the still image data. When data of each frame arechanged during the predetermined frame periods, the image data aredetermined to be the moving image data. When the image data are thestill image data, the still image determining unit 172 may output astill image flag to notify that the image data are the still image data.

The driving frequency deciding unit 173 may decide the driving frequencyby analyzing the image data when the image data are the still imagedata. The driving frequency deciding unit 173 may decide the drivingfrequency as the low frequency to reduce the power consumption, becausedata of each frame of the image data during the predetermined frameperiods are the same data as each other when the image data are stillimage data. In a display device, when frequency of the image data islower than a certain level, the flicker may occur. Therefore, in anexemplary embodiment, the driving frequency deciding unit 173 may decidethe driving frequency within a range that is predetermined forflicker-free driving, e.g., a predetermined frequency range that allowsthe still image data to be displayed without flicker. In one exemplaryembodiment, for example, the driving frequency deciding unit 173 maycalculate grayscale of the image data, and decide the driving frequencycorresponding to the grayscale using the flicker profile.

The frequency information providing unit 174 may provide the decideddriving frequency as the driving frequency information to a frequencyinformation receiving unit 210. The frequency information providing unit174 may provide the decided driving frequency through various kinds ofmethods according to types of the processor 200A or the controller 170A.In one exemplary embodiment, for example, the driving frequency isprovided from the frequency information providing unit 174 to thefrequency information receiving unit 210 via a private channel, a mobileindustry processor interface (“MiPi”), an AUX channel of the displayport, etc. In one exemplary embodiment, for example, the frequencyinformation providing unit 174 may provide the driving frequency to thefrequency information receiving unit 210 when the driving frequency ischanged. In one exemplary embodiment, for example, the frequencyinformation providing unit 174 may recognize changing of the drivingfrequency determined by the driving frequency deciding unit 173, andprovide the driving frequency to the frequency information receivingunit 210.

The timing controller 178 may generate control signals based on theimage data, and provide the control signals to the data driving unit andthe scan driving unit. To display the image, the timing controller 178may provide a data signal, a horizontal start signal and a first clocksignal to the data driving unit, and may provide a vertical start signaland a second clock signal to the scan driving unit. In such anembodiment, the timing controller 178 may not include the frame memory,thereby reducing manufacturing cost of display device and reducing thepower consumption.

In an exemplary embodiment, as shown in FIG. 2 , the processor 200A mayinclude a frequency information receiving unit 210 and an image datatransferring unit 240.

The frequency information receiving unit 210 may receive the drivingfrequency information based on the driving frequency from the frequencyinformation providing unit 174 to adjust the frequency of the imagedata. The frequency information receiving unit 210 may receive thedriving frequency as the driving frequency information from thefrequency information providing unit 174 to adjust the frequency of theimage data. In one exemplary embodiment, for example, the frequencyinformation receiving unit 210 may periodically send a driving frequencyproviding request, that is, a request for providing a driving frequency,to the frequency information providing unit 174, and the frequencyinformation providing unit 174 may provide the driving frequency to thefrequency information receiving unit 210 in response to the drivingfrequency providing request. In one exemplary embodiment, for example,the frequency information receiving unit 210 may send the drivingfrequency providing request to the frequency information providing unit174 every predetermined time period, e.g., hour, and check a change inthe driving frequency.

The image data transferring unit 240 may adjust the frequency of theimage data to the driving frequency, and transfer the image data withthe driving frequency to the image data receiving unit 171. When theimage data are still image data, the image data transferring unit 240may adjust the frequency of the image data to the driving frequency thatis a low frequency without the flicker. Herein, a low frequency means apredetermined frequency lower than the normal driving frequency, and alow frequency without the flicker means a low frequency that effectivelyprevents a viewer to recognize a flicker when the image data isdisplayed based thereon. Therefore, in such an embodiment, the imagedata transferring unit 240 transfers the image data with a lowfrequency, thereby reducing the power consumption and preventing theflicker.

FIG. 3 is a graph showing an exemplary embodiment of a flicker profileto decide a driving frequency in the electronic device of FIG. 1 .

Referring to FIG. 3 , a driving frequency of image data provided to thedisplay device by processor may be decided using a flicker profile. Theflicker profile may include driving frequencies corresponding to agrayscale of the image data to effectively prevent the flicker. Thus,the flicker profile may include information of minimum frequency withwhich the image data does not cause flicker. Therefore, the grayscale ofthe image data is calculated by analyzing the image data, and thedriving frequency is derived from the flicker profile and the grayscaleof the image data. In one exemplary embodiment, for example, when theimage data has a first grayscale that is a relatively low grayscale, thedriving frequency may have a first frequency that is relatively low. Insuch an embodiment, when the image data has a second grayscale that is amiddle grayscale, the driving frequency may have a second frequency thatis relatively high with respect to the first frequency.

The flicker profile may be differently set based on the display device,because characteristics of the display device are different by size ortype of the display device. In an exemplary embodiment, the flickerprofile may be stored in a memory of the display device. In oneexemplary embodiment, the flicker profile may be stored in an erasableprogrammable read only memory (“EPROM”) connected to the controller ofthe display device. In an exemplary embodiment, where the processor hasno direct access to the flicker profile of the display device, thedisplay device may provide the flicker profile or the driving frequencydecided using the flicker profile to the processor for a low frequencydriving.

FIG. 4 is a diagram illustrating an exemplary embodiment of a lowfrequency driving between the processor and the display device of FIG. 2.

Referring to FIG. 4 , in an exemplary embodiment, the image datatransferring unit may adjust the frequency of the image data to thedriving frequency by masking the image data.

In one exemplary embodiment, for example, frequency of original imagedata may be about 60 hertz (Hz). In such an embodiment, when theoriginal image data are the still image data, a still image data flag isset to high. The driving frequency is decided or set as about 10 Hzcorresponding to the grayscale of the original image data using theflicker profile. In such an embodiment, the output image data aregenerated by masking the original image data. Therefore, the processormay adjust the frequency of the output image data to the drivingfrequency lower than original frequency without using additional memoryby masking the original image data.

FIG. 5 is a block diagram illustrating another exemplary embodiment of aprocessor and a controller of a display device of the electronic deviceof FIG. 1 .

Referring to FIG. 5 , in an exemplary embodiment, a controller 170B ofthe display device may provide the driving frequency to the processor200B, such that the processor 200B may adjust a frequency of the imagedata based on the driving frequency.

The controller 170B may include an image data receiving unit 171, adriving frequency deciding unit 173, a frequency information providingunit 174 and a timing controller 178. The controller 170B of anexemplary embodiment as shown in FIG. 5 is substantially the same as thecontroller in an exemplary embodiment described above with reference toFIG. 2 , except that the controller 170B does not include the stillimage determining unit. The same or like elements shown in FIG. 5 havebeen labeled with the same reference characters as used above todescribe the controller in an exemplary embodiment as shown in FIG. 2 ,and any repetitive detailed description thereof will hereinafter beomitted or simplified.

The image data receiving unit 171 may receive the image data from animage data transferring unit 240. The image data receiving unit 171 maytransfer the image data to the driving frequency deciding unit 173 todecide the driving frequency between the processor 200B and displaydevice. In one exemplary embodiment, for example, when the still imageflag of the image data is high, that is, when the image data are thestill image data, the image data receiving unit 171 may transfer theimage data to the driving frequency deciding unit 173.

The driving frequency deciding unit 173 may decide the driving frequencyby analyzing the image data when the image data are the still imagedata.

The frequency information providing unit 174 may provide the decideddriving frequency as the driving frequency information to a frequencyinformation receiving unit 210.

The timing controller 178 may generate control signals based on theimage data, and provide the control signals to the data driving unit andthe scan driving unit.

The processor 200B may include a frequency information receiving unit210, a still image determining unit 220 and an image data transferringunit 240. The processor 200B in an exemplary embodiment as shown in FIG.5 is substantially the same as the processor of an exemplary embodimentdescribed above with reference to FIG. 2 , except that the still imagedetermining unit 220 is added. The same or like elements shown in FIG. 5have been labeled with the same reference characters as used above todescribe the processor and the processor in an exemplary embodiment asshown in FIG. 2 , and any repetitive detailed description thereof willhereinafter be omitted or simplified.

The frequency information receiving unit 210 may receive the drivingfrequency as the driving frequency information from the frequencyinformation providing unit 174 to adjust the frequency of the imagedata. In one exemplary embodiment, for example, the frequencyinformation receiving unit 210 may send a driving frequency providingrequest to check changing of the driving frequency.

The still image determining unit 220 may determine whether the imagedata are still image data. In one exemplary embodiment, for example, thestill image determining unit 220 may analyze the frame data of the imagedata. In such an embodiment, when data of each frame are not changedduring predetermined frame periods, then the image data are determinedto be the still image data. In such an embodiment, when data of eachframe are changed during the predetermined frame periods, the image dataare determined to be the moving image data. When the image data are thestill image data, the still image determining unit 172 may output astill image flag to notify that the image data are the still image data.

The image data transferring unit 240 may adjust the frequency of theimage data to the driving frequency, and transfer the image data withthe driving frequency to the image data receiving unit 171. When theimage data are still image data, the image data transferring unit 240may adjust the frequency of the image data to the driving frequency thatis a low frequency without the flicker.

In an exemplary embodiment, as shown in FIG. 5 , when the processor 200Bincludes the still image determining unit 220 to determine whether theimage data are the still image data, load of the display device may berelieved, as the still image detection is performed in the processor200B.

FIG. 6 is a block diagram illustrating still another exemplaryembodiment of a processor and a controller of a display device of anelectronic device of FIG. 1 .

Referring to FIG. 6 , in an exemplary embodiment, a controller 170C ofthe display device may provide the flicker profile to the processor200C, such that the processor 200C may adjust a frequency of the imagedata based on the flicker profile.

The controller 170C may include an image data receiving unit 171, aprofile providing unit 175 and a timing controller 178.

The image data receiving unit 171 may receive the image data from theprocessor 200C. The image data receiving unit 171 may transfer the imagedata to the timing controller 178 to provide control signalscorresponding to the image data to the scan driving unit and the datadriving unit.

In an exemplary embodiment, as shown in FIG. 6 , the profile providingunit 175 may provide a flicker profile of the display device as thedriving frequency information to a profile receiving unit 215. Theflicker profile may be stored in the memory such as an EPROM connectedto the profile providing unit 175. The profile providing unit 175 mayprovide the flicker profile to the profile receiving unit 215 through amethod among various kinds of methods, which may be determined based ontypes of the processor 200C or the controller 170C. In one exemplaryembodiment, for example, the flicker profile is provided from theprofile providing unit 175 to the profile receiving unit 215 via aprivate channel, a MiPi, an AUX channel of the display port, etc. In oneexemplary embodiment, for example, the profile providing unit 175 mayprovide the flicker profile as the driving frequency information to theprofile receiving unit 215 when the electronic device or the displaydevice is initialized. In an exemplary embodiment, where the flickerprofile does not need to change, the profile providing unit 175 providesthe flicker profile to the profile receiving unit 215 only when theelectronic device or the display device is initialized, thereby reducingthe load of the processor 200C and the display device.

The timing controller 178 may generate control signals based on theimage data, and provide the control signals to the data driving unit andthe scan driving unit. In such an embodiment, the timing controller 178is substantially the same as the timing controller in the exemplaryembodiments described above, and any repetitive detailed descriptionthereof will be omitted.

The processor 200C may include a profile receiving unit 215, a stillimage determining unit 220, a driving frequency deciding unit 230 and animage data transferring unit 240.

The profile receiving unit 215 may receive the image data from theprofile providing unit 175.

The still image determining unit 220 may determine whether the imagedata are still image data. In such an embodiment, the still imagedetermining unit 220 is substantially the same as the still imagedetermining unit in the exemplary embodiments described above, and anyrepetitive detailed description thereof will be omitted.

The driving frequency deciding unit 230 may calculate a grayscale of theimage data when the image data are the still image data, and to decidethe driving frequency corresponding to the grayscale of the image datausing the flicker profile received from the profile receiving unit 215.The driving frequency deciding unit 230 may decide the driving frequencythat is a low frequency to reduce the power consumption, because data offrames of the image data are substantially the same as each other whenthe image data are still image data. The driving frequency deciding unit230 may decide the driving frequency within a range that ispredetermined for flicker-free driving.

The image data transferring unit 240 may adjust the frequency of theimage data to the driving frequency, and transfer the image data withthe driving frequency to the image data receiving unit 171. When theimage data are still image data, the image data transferring unit 240may adjust the frequency of the image data to the driving frequency thatis a low frequency without the flicker. Therefore, the image datatransferring unit 240 transfers the image data with a low frequency,thereby reducing the power consumption and effectively preventing theflicker.

In an exemplary embodiment, as shown in FIG. 6 , the processor 200Cdecides the driving frequency as low driving frequency, thereby reducingload of the display device. In such an embodiment, efficiency of theelectronic device may be improved, by providing the flicker profile tothe processor 200C from the display device at once.

FIG. 7 is a block diagram illustrating still another exemplaryembodiment of a processor and a controller of a display device of anelectronic device of FIG. 1 . FIG. 8 is a diagram illustrating anexemplary embodiment of a low frequency driving between the processorand the display device of FIG. 7 .

Referring to FIGS. 7 and 8 , in an exemplary embodiment, a processor200D may include an image data memory 260, such that frequency of imagedata is adjusted to various driving frequencies in the processor 200D.

In such an embodiment, as shown in FIG. 7 , the controller 170D of thedisplay device may provide the driving frequency to the processor 200D,such that the processor 200D may adjust a frequency of the image databased on the driving frequency from the controller 170D.

The controller 170D may include an image data receiving unit 171, astill image determining unit 172, a driving frequency deciding unit 173,a frequency information providing unit 174 and a timing controller 178.The controller 170D of the exemplary embodiment shown in FIG. 7 issubstantially the controller of the exemplary embodiments describedabove with reference to FIG. 2 . Therefore, the same or like elementsshown in FIG. 7 have been labeled with the same reference characters asused above to describe the controller of the exemplary embodiments shownin FIG. 3 , and any repetitive detailed description thereof willhereinafter be omitted or simplified.

The processor 200D may include a frequency information receiving unit210, an image data transferring unit 240 and the image data memory 260.The processor 200D of the exemplary embodiment shown in FIG. 7 issubstantially the same as the processor of the exemplary embodimentsdescribed above with reference to FIG. 2 , except for the image datamemory 260. Therefore, the same or like elements shown in FIG. 7 havebeen labeled with the same reference characters as used above todescribe the processor of the exemplary embodiments shown in FIG. 3 ,and any repetitive detailed description thereof will hereinafter beomitted or simplified.

The frequency information receiving unit 210 may receive the drivingfrequency information based on the driving frequency from the frequencyinformation providing unit 174 to adjust the frequency of the imagedata.

The image data memory 260 stores the image data. The image data memory260 may temporally store the image data to adjust the frequency of theimage data to various driving frequencies. In one exemplary embodiment,for example, the image data memory 260 may be a nonvolatile memory suchas flash memory, resistance random access memory (“RRAM”), nano floatinggate memory (“NFGM”), polymer random access memory (“PoRAM”), magneticrandom access memory (“MRAM”), and ferroelectric random access memory(“FRAM”). Also, the image data memory 260 may be a volatile memory suchas dynamic random access memory (“DRAM”), static random access memory(“SRAM”), and mobile DRAM. In an exemplary embodiment, as shown in FIG.7 , the image data memory 260 is disposed in the processor 200D, but notbeing limited thereto. In an alternative exemplary embodiment, the imagedata memory 260 may be disposed outside of the processor 200D.

The image data transferring unit 240 may adjust the frequency of theimage data to the driving frequency, and transfer the image data withthe driving frequency to the image data receiving unit 171.

As shown in FIG. 8 , the image data transferring unit 240 may adjust thefrequency of the image data to the driving frequency using the imagedata stored in the image data memory 260.

In one exemplary embodiment, for example, frequency of original imagedata may be 60 Hz. When the original image data are the still imagedata, a still image data flag is set to high. The driving frequency maybe decided or set as 40 Hz corresponding to the grayscale of theoriginal image data using the flicker profile. In the processor of anexemplary embodiment shown in FIG. 2 that does not include the imagedata memory, frequency of output image data may not be adjusted to 40 Hzby masking the image data, because 40 Hz is not divisor of 60 Hz. Thus,in such an embodiment, when the frequency of the output image data isadjusted by the masking process, the frequency of the output image dataonly have frequencies that are divisors of the frequency of the originalimage data. In an alternative exemplary embodiment, as shown in FIG. 7 ,the processor 200D having the image data memory 260 may store the imagedata in the image data memory 260, thereby adjusting the frequency ofthe output image data to various frequencies using the image data storedin the image data memory 260.

FIG. 9 is a block diagram illustrating another exemplary embodiment ofan electronic device according to the invention.

Referring to FIG. 9 , in an exemplary embodiment, an electronic device1000B may include a display device 100B and a processor 200.

The display device 100B may include a display panel 110B and a pluralityof integration driving units 180-1 through 180-n.

The display panel 110B may include a plurality of pixels to displayimage corresponding to the image data DATA. The display panel 110B mayinclude a plurality of display regions 115-1 through 115-n. Each of thedisplay regions 115-1 through 115-n may be respectively coupled to theintegration driving units 180-1 through 180-n via driving lines.

In an exemplary embodiment, each of the integration driving units 180-1through 180-n may provide a driving frequency information FRI to theprocessor 200, and receive the image data DATA with the drivingfrequency determined based on the driving frequency information FRI fromthe processor 200. In such an embodiment, each of the integrationdriving units 180-1 through 180-n have a structure integrated controllerand driving unit to provide control signals corresponding to the imagedata DATA to the pixels of the coupled display region. In one exemplaryembodiment, for example, the first integration driving unit 180-1 mayhave a structure in which a controller and a data driving unit areintegrated, and provide data signal, clock signal and start signalcorresponding to the image data DATA, to the first display region 115-1.

In such an embodiment, the display device 100B may further include thescan driving unit or the power supply unit, for example.

The processor 200 may receive the driving frequency information FRI fromeach of the integration driving units 180-1 through 180-n and adjustfrequency of the image data DATA based on the highest frequency amongthe frequencies corresponding to the driving frequency information FRI.Thus, the processor 200 may adjust the frequency of the image data DATAbased on the highest frequency among the driving frequenciescorresponding to the driving frequency information FRI to effectivelyprevent the flicker in the entire display panel 110B. In such anembodiment, the processor 200 may transfer the image data DATA with alow frequency to the display device 100B.

FIG. 10 is a block diagram illustrating an exemplary embodiment of aprocessor and an integration driving units of a display device of anelectronic device of FIG. 9 .

Referring to FIG. 10 , in an exemplary embodiment, each of theintegration driving units 180-1 through 180-n of the display device mayprovide the driving frequency to the processor 200E, such that theprocessor 200E may adjust a frequency of the image data based on thedriving frequency from each of the integration driving units 180-1through 180-n.

Each of the integration driving units 180-1 through 180-n may include animage data receiving unit 181, a still image determining unit 182, adriving frequency deciding unit 183, a frequency information providingunit 184 and a timing controller 188.

The image data receiving unit 181 may receive the image data from theprocessor 200E. The still image determining unit 182 may determinewhether the image data from the processor 200E are still image data. Thedriving frequency deciding unit 183 may decide the driving frequency byanalyzing the image data when the image data are the still image data.The frequency information providing unit 184 may provide the decideddriving frequency as the driving frequency information to a frequencyinformation receiving unit 210. The timing controller 188 may generatecontrol signals based on the image data, and provide the control signalsto the display panel.

The image data receiving unit 181, the still image determining unit 182,the driving frequency deciding unit 183, the frequency informationproviding unit 184, and the timing controller 188 of the exemplaryembodiment shown in FIG. 10 are substantially the same as the stillimage determining unit, the driving frequency deciding unit, thefrequency information providing unit and the timing controller of theexemplary embodiment described above with reference to FIG. 2 , exceptthat each of the integration driving units 180-1 through 180-nrespectively calculate the driving frequencies and respectively providethe driving frequencies to the processor 200E.

The processor 200E may include a frequency information receiving unit210 and an image data transferring unit 240.

The frequency information receiving unit 210 may receive the drivingfrequency information based on the driving frequencies from each thefrequency information providing unit 184 of the integration drivingunits 180-1 through 180-n to adjust the frequency of the image data.

The image data transferring unit 240 may adjust the frequency of theimage data to the driving frequency, and transfer the image data withthe driving frequency to each the image data receiving unit 181 of theintegration driving units 180-1 through 180-n. The image datatransferring unit 240 may adjust the frequency of the image data basedon the highest frequency among the driving frequencies received from theintegration driving units 180-1 through 180-n. Thus, the image datatransferring unit 240 may adjust the frequency of the image data basedon the highest frequency among the driving frequencies corresponding tothe driving frequency information FRI to effectively prevent the flickerin the entire display panel.

FIG. 11 is a flow chart illustrating an exemplary embodiment a method ofoperating an electronic device according to the invention.

Referring to FIG. 11 , an exemplary embodiment of a method of operatingan electronic device performs a low frequency driving between theprocessor and the display device by sharing the driving frequencyinformation between the processor and the display device. Therefore,such an embodiment of the method of operating the electronic device mayallow the electronic device to reduce the power consumption thereof andto effectively prevent the flicker.

In an exemplary embodiment, it is determined whether image data arestill image data (S110). In one exemplary embodiment, for example, ifdata of each frame of the image data are not changed duringpredetermined frame periods, then the image data are determined to bethe still image data. In such an embodiment, if data of each frame ofthe image data are changed during predetermined frame periods, then theimage data are determined as the moving image data. In such anembodiment, the determining whether image data are still image data(S110) may be performed by the processor or the display device.

In such an embodiment, when the image data are the still image data,grayscale of the image data may be calculated (S120). In such anembodiment, the driving frequency corresponding to the grayscale may bedecided using the flicker profile (S125). In such an embodiment, thedriving frequency is determined as a low frequency to reduce the powerconsumption. However, in a display device, when the frequency of theimage data is lower than a certain level, the flicker may occur.Therefore, in an exemplary embodiment, the driving frequency is decidedor set as a frequency within a range that is predetermined forflicker-free driving. In an exemplary embodiment, the calculating thegrayscale (S120) and the deciding the driving frequency (S125) may beperformed by the processor or the display device. In such an embodiment,the flicker profile is provided from the display device to the processorin advance to perform the calculating the grayscale (S120) and thedeciding the driving frequency (S125) by the processor.

The frequency of the image data may be adjusted to the driving frequencyby the processor (S130). When the image data are the still image data,the processor may adjust the frequency of the image data to the drivingfrequency that is a low frequency. In one exemplary embodiment, forexample, the driving frequency may be decided by the display device, theprocessor may receive the driving frequency from the display device andadjust the frequency of image data to the driving frequency lower thanoriginal frequency of the image data. In one exemplary embodiment, forexample, the frequency of the image data may be adjusted to the drivingfrequency by masking the image data. In such an embodiment, the methodof adjusting the frequency of the image data is substantially the sameas the method in exemplary embodiments described above, and anyrepetitive detailed description thereof will be omitted.

In an exemplary embodiment, the processor may transfer the image datawith the adjusted frequency to the display device (S140). The displaydevice may display an image corresponding to the image data (S150).

Therefore, an exemplary embodiment of the method of operating theelectronic device performs a low frequency driving between the processorand the display device using the flicker profile of the display device.In an exemplary embodiment, the method of operating the electronicdevice performs a low frequency driving without using a frame memory,thereby reducing manufacturing cost and reducing the power consumption.

Exemplary embodiments of the invention may be applied to an electronicdevice including the display device, e.g., a cellular phone, a smartphone, a smart pad, a personal digital assistant (“PDA”), etc.

The foregoing is illustrative of exemplary embodiments and is not to beconstrued as limiting thereof. Although a few exemplary embodiments havebeen described, those skilled in the art will readily appreciate thatmany modifications are possible in the exemplary embodiments withoutmaterially departing from the novel teachings and advantages of theinvention. Accordingly, all such modifications are intended to beincluded within the scope of the invention as defined in the claims.Therefore, it is to be understood that the foregoing is illustrative ofvarious exemplary embodiments and is not to be construed as limited tothe specific exemplary embodiments described therein, and thatmodifications to the exemplary embodiments described herein, as well asother exemplary embodiments, are intended to be included within thescope of the appended claims.

What is claimed is:
 1. An electronic device comprising: a display deviceconfigured to receive image data from a processor, to receive a flickerprofile from a memory, to determine a driving frequency by analyzing theimage data using the flicker profile, to provide driving frequencyinformation corresponding to the driving frequency to the processor, andto display an image corresponding to the image data; the memoryconnected to or included in the display device and configured to storethe flicker profile, the memory being directly inaccessible to theprocessor; and the processor configured to receive the driving frequencyinformation from the display device, to adjust a frequency of the imagedata to the driving frequency based on the driving frequencyinformation, and to transmit the image data to the display device at thedriving frequency.
 2. The electronic device of claim 1, wherein thedisplay device is configured to determine the driving frequency based agrayscale of the image data and the flicker profile.
 3. The electronicdevice of claim 2, wherein the flicker profile includes information ofminimum frequency with which the grayscale of the image data does notcause flicker.
 4. The electronic device of claim 1, wherein the displaydevice is configured to determine whether the image data are still imagedata.
 5. The electronic device of claim 1, wherein the processor isconfigured to determine whether the image data are still image data. 6.The electronic device of claim 1, wherein the processor is configured toadjust the frequency of the image data to the driving frequency bymasking the image data.
 7. The electronic device of claim 1, wherein theprocessor is configured to adjust the frequency of the image data to thedriving frequency by using the image data stored in an image data memoryincluded in the processor.
 8. The electronic device of claim 1, whereinthe display device includes first to n-th display regions and first ton-th integration driving units for driving the first to n-th displayregions, respectively, wherein the first to n-th integration drivingunits are configured to provide first to n-th driving frequenciescorresponding to the driving frequency information to the processor, andwherein the processor is configured to adjust the frequency of the imagedata to a highest frequency among the first to n-th driving frequencies.9. An electronic device comprising: a display device configured toreceive image data from a processor, to receive a flicker profile from amemory, to transmit the flicker profile to the processor, and to displayan image corresponding to the image data; the memory connected to orincluded in the display device and configured to store the flickerprofile, the memory being directly inaccessible to the processor; andthe processor configured to receive the flicker profile from the displaydevice, to determine a driving frequency by analyzing the image datausing the flicker profile, to adjust a frequency of the image data tothe driving frequency, and to transmit the image data to the displaydevice at the driving frequency.
 10. The electronic device of claim 9,wherein the processor is configured to determine the driving frequencybased a grayscale of the image data and the flicker profile.
 11. Theelectronic device of claim 10, wherein the flicker profile includesinformation of minimum frequency with which the grayscale of the imagedata does not cause flicker.
 12. The electronic device of claim 9,wherein the processor is configured to determine whether the image dataare still image data.
 13. The electronic device of claim 9, wherein theprocessor is configured to adjust the frequency of the image data to thedriving frequency by masking the image data.
 14. The electronic deviceof claim 9, wherein the processor is configured to adjust the frequencyof the image data to the driving frequency by using the image datastored in an image data memory included in the processor.
 15. Theelectronic device of claim 9, wherein the display device is configuredto transmit the flicker profile to the processor when the electronicdevice or the display device is initialized.